Clinical Correlation between HLA-B27 and Inflammatory Marker in Case of Ankylosing Spondylitis (AS)

Ankylosing spondylitis (AS) shows a strong correlation with human leukocyte antigen (HLA-B27), and number of evidence suggests that the B27 gene may have a pathogenic role in the development of AS and HLA-B27 has a tendency for familial association [1-3]. The association of HLA-B27 with Ankylosing spondylitis was first described in 1973 [4], and is among the strongest described for a HLA locus. The frequency of HLA-B27 with AS among Indian population varies from 40 to 94% as compared to 1.4-8% of the general population [5]. HLA-B27 is a unique HLA class I molecule, not only because of its high association with AS but also has characteristically different amino acid composition from other class I molecules. There are two important characteristic structures which are different from others: the presence of B pocket and the free thiol group of Cys67 [6,7]. We performed this study to find out pathophysiological differences between B27+ and B27patients with AS and relate these differences to the serum concentrations of CRP, ESR (erythrocyte sedimentation rate) and RF (Rheumatoid factor) to determine whether the B27 status and presence or absence of disease activity could predict the concentrations of CRP and ESR. ESR and CRP are two currently used biomarkers for the evaluation of inflammatory activity of the disease. However, these biomarkers do not have the most ideal specificity, sensitivity, and reproducibility characteristics.